Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098708)

high Nessus Plugin ID 340188

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-098708 advisory.

In the Linux kernel, the following vulnerability has been resolved:

drbd: add missing kref_get in handle_write_conflicts

With `two-primaries` enabled, DRBD tries to detect concurrent writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed.

In handling superseeded writes, we forgot a kref_get, resulting in a premature drbd_destroy_device and use after free, and further to kernel crashes with symptoms.

Relevance: No one should use DRBD as a random data generator, and apparently all users of two-primaries handle concurrent writes correctly on layer up.
That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node.

Which means that other than for test cases, this code path is never taken in real life.

FYI, in DRBD 9, things are handled differently nowadays. We still detect write conflicts, but no longer try to be smart about them.
We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected kernel package.

Plugin Details

Severity: High

ID: 340188

File Name: unity_linux_UTSA-2026-098708.nasl

Version: 1.1

Type: Local

Family: Unity Linux Local Security Checks

Published: 8/26/2026

Updated: 8/26/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 57.83

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2025-38708

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/10/2026

Vulnerability Publication Date: 9/4/2025

Reference Information

CVE: CVE-2025-38708

Detections

Analytics